The ratio of the sides of the room are roughly 3:1 (3*178=534). The paper needs to accommodate this 3:1 scaling. If the whole of the length of the paper (11") represents the long side of the room (533") then the short side of the room (178") would be 11/3" long = 3.6" approx. 11" is 110 tenths of an inch and if we divide 533 by 110 we get about 4.8. So 0.1" could be used to represent 5" of the room measurements. So 11" would accommodate a room length of 110*5=550" which is a little more than 533". 8.5" would accommodate 85*5=425" and we only need 178". So a rectangle equivalent to room size of 200" by 550" would be a rectangle of 4" by 11" on paper. The scale map of the room can be positioned with the long side of the room placed about 2" from the long side of the paper and running the whole length of the paper. The short side of the room is part of the width of the paper and we only need 4 inches, so from the 11" line sitting 2" from the edge of the long side of the paper we only need a scale running up to 6" from the long side of the paper. On the "axes" we can mark a few measurements. Each tenth of an inch represents 5" of the room so 0.2" represents 10" of room. So divide the scales into 0.2" divisions. On the long side we have 0, 10, 20, 30, up to 550 and on the short side 0, 10, 20, up to 200 in 0.2" steps. To place measurements from the actual room on to the map we divide the measurement in inches by 10 and then multiply by 0.2 to get the measurement on the map (or we could simply divide by 50, because the scale is 1:50). Example: 178" divided by 10 is 17.8 multiplied by 0.2=3.56" on the map; 533/50=10.66". You should find that these measurements should correspond to the divisions you marked on the map.